Just go with the colour that appeals to you most I doubt any will look incongruous. The grass that's next to your house is green and doesn't look odd.
What I recommend my customers do is obtain a few samples and place them against the house near the front door. Eventually one of the colours will catch your eye more than the others.
Natural or fired clay paving will retain their colours. More than likely will need a similar cleaning and maintenance program as concrete blocks.